The Sibley-Munroe checklist was a landmark document in the study of birds. It drew on extensive DNA-DNA hybridisation studies to reassess the relationships between modern birds.
... from 45 to 64, and 14.1% who are 65 years of age or older. The median age is 28 years. For every 100 females there are 82.8 males. For every 100 females age 18 and ...